tag:blogger.com,1999:blog-21605329.post161352457341213283..comments2018-03-19T13:50:29.778-07:00Comments on The Neurocritic: Stem Cells for Peter's McStrokeThe Neurocritichttp://www.blogger.com/profile/08010555869208208621noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-21605329.post-70295353243199110692008-03-01T11:59:00.000-08:002008-03-01T11:59:00.000-08:00OK, here are the answers to Lazily's questions, as...OK, here are the answers to Lazily's questions, as far as I can tell.<BR/><BR/>(1) Sham-operated controls: YES<BR/><BR/><I>As a control group, we used rats subjected to ischemia and injected with the vehicle (n = 7).</I><BR/><BR/>This seems to have been only for the evaluation of sensorimotor function.<BR/><BR/>(2) Electrophysiology: NO [not really fair to ask the same investigators to do this].<BR/><BR/>(3a) Conversion rate <I>in vitro</I>:<BR/><BR/><I>Immunocytochemical analysis (Figure 2B–F) of 10 day-old cultures demonstrated that the proportion of nestin+ cells was 36.6±2.7%, 62.5±2.8% expressed the neuronal marker TuJ1, 1.9±0.3% expressed the astrocytic marker GFAP and 7.1±0.4% were oligodendrocytes and expressed galactocerebrocide (GC) (Figure 2F). A subset (9.8±1.6%) of the GFAP+ astrocytes co-expressed nestin [a neural-specific gene]</I>.<BR/><BR/>(3b) Survival and functional engraftment <I>in vivo</I>:<BR/><BR/><I>Grafted SD56 hNSCs, identified with hNuc, demonstrated a 37.0±15.8% survival rate and a remarkable dispersion toward the stroke-damaged tissue with no sign of overgrowth or tumorigenesis. The majority of grafted cells (61.2±4.7%) migrated at least 200 µm away from the injection site and penetrated an average distance of 806.4±49.3 µm into the stroke-damaged tissue</I>.<BR/><BR/>(4) Anything to prevent proliferation of animal cells: ?? [don't think so].<BR/><BR/>(5) Transplanted cells a source of neurotrophic factors: don't know. They were cultured with EGF and FGF2, but don't know about transplanted cells themselves.<BR/><BR/>You can <A HREF="http://www.plosone.org/user/secure/secureRedirect.action?goTo=%2Farticle%2Finfo%3Adoi%2F10.1371%2Fjournal.pone.0001644" REL="nofollow">make a general comment</A> on the paper if you'd like...The Neurocritichttps://www.blogger.com/profile/08010555869208208621noreply@blogger.comtag:blogger.com,1999:blog-21605329.post-45765475586586156672008-03-01T11:13:00.000-08:002008-03-01T11:13:00.000-08:00I was pretty lazy too (i.e., I didn't read the pap...I was pretty lazy too (i.e., I didn't read the paper, which is beyond my area of expertise). I spent a lot more time on the Family Guy image...<BR/><BR/>Here are the <A HREF="http://www.plosone.org/annotation/listThread.action?inReplyTo=info%3Adoi%2F10.1371%2Fannotation%2F6783242e-b769-4516-8b3a-07407002cbe1&root=info%3Adoi%2F10.1371%2Fannotation%2F6783242e-b769-4516-8b3a-07407002cbe1" REL="nofollow">comments of Referee 1</A> (not that they ask the same questions as you, however).The Neurocritichttps://www.blogger.com/profile/08010555869208208621noreply@blogger.comtag:blogger.com,1999:blog-21605329.post-17755559632291390042008-02-29T20:12:00.000-08:002008-02-29T20:12:00.000-08:00OK, I am lazy tonight. Did the authors have sham-o...OK, I am lazy tonight. Did the authors have sham-operated rodents to compare the stem-implanted rodents with? Was there any electrophysiology done on the purported replacement neurons? What was the conversion rate of the NSCs to presumptive neurons? Did they do anything to stop the proliferation of the animal stem cells near the stroke damage? Is there any evidence that the transplanted cells, whatever their differentiation state, were not a source of (say) neurotrophic factors?<BR/><BR/>I admit these are annoying questions, but we should be getting to the point where these are the questions to ask. I can think of some interesting genetic manipulations you could try to tease apart the question of detecting activity in animal vs. human neurons in these animals (one idea: do the experiments in a line where you have messed with the locus of the early intermediate gene arc so that you will end up with arc mRNAs that differ in sequence between the hNSC derived neurons and animal ones and then use appropriately designed fluorescent probes...not that easy, but problably worth it).lazily anonymousnoreply@blogger.comtag:blogger.com,1999:blog-21605329.post-81944043243446140642008-02-24T11:09:00.000-08:002008-02-24T11:09:00.000-08:00Thanks for sending the link to your poem. I wish t...Thanks for sending the link to your poem. I wish the research had reached an advanced enough stage to help you now. I also wish you luck in <A HREF="http://scottthong.wordpress.com/2007/04/16/back-to-the-future-stem-cells/#comment-23615" REL="nofollow">your quest to educate "Christians"</A> who value stem cells more than living, suffering human beings.<BR/><BR/><I>“...fuzzy stem-cell thinking –<BR/>The kind that makes us sick.”</I>The Neurocritichttps://www.blogger.com/profile/08010555869208208621noreply@blogger.comtag:blogger.com,1999:blog-21605329.post-61794829709679198592008-02-24T07:58:00.000-08:002008-02-24T07:58:00.000-08:00But stem cells themselves are vocal opponents of s...But stem cells themselves are <A HREF="http://www.originalfaith.com/blog/2008/02/panel-of-stem-cells-meets-to-discuss.html" REL="nofollow">vocal opponents of such research</A>.paul maurice martinhttp://www.originalfaith.com/noreply@blogger.com